Table of ContentsView All
View All
Table of Contents
Symptoms
Causes
Diagnosis
Treatment
Interpreting the Results
Frequently Asked Questions
Anadenomatous polyp, also known as an adenoma, is anabnormal growththat forms on the colon’s lining(large intestine).These polyps are common, comprising around 70% of allcolon polyps. Roughly one-third to one-half of all people will develop one or more adenomatous polyps in their lifetime.
This article describes the causes and symptoms of adenomatous polyps as well as how these polyps are diagnosed and treated. It also walks you through what a pathology report means if a polyp is found during a routinecolonoscopy.
Verywell / Julie Bang
Adenomatous Polyp Symptoms
Adenomatous polyps typically do not cause symptoms unless they progress tocolon cancer. Even then, there may be no sign of a problem until the malignancy is advanced. This is why colon cancer screenings are so important.
Among the possible symptoms of an adenomatous polyp are:
What Are the Types of Colon Polyps?
What Causes Adenomatous Polyps?
Adenomatous polyps can form anywhere in the large intestine. There is no known way to prevent polyps from growing altogether, although some knownrisk factorsare modifiable and can be avoided.
Gene mutationscan contribute to the formation of adenomatous polyps because they cause cells to divide in an unregulated way. Some of these mutations (such as APC, TP53, and KRAS) are associated with an increased risk of colon cancer.
While there’s no way to pin down the specific cause of polyp formation, there are a few things that can increase your risk of developing polyps and colorectal cancer:
What Are the Different Types of Colon Polyps?
If a polyp is found, it may or may not be removed using a procedure known as apolypectomy. The decision to remove or not remove a polyp is based on the size of the growth as well as its location and appearance.
Areas of concern within the colon will be marked with a tattoo and noted in thepathology report. In this way, the gastroenterologist can return to the area during the next scheduled colonoscopy to check for any changes.
Fewer than 5% of adenomatous polyps progress to cancer over the course of seven to 10 years.
Updated Colon Cancer Screening Recommendations
Adenomatous polyps are found during various colorectal cancer screening tests. It is important for people to receive screening for colorectal cancer at regular intervals based on recommendations from a physician.
Screening recommendations from the American Cancer Society (ACS)and U.S. Preventive Services Task Force (USPSTF)were updated in 2021. Both now recommend colon cancer screening starting at age 45 or younger for those at an increased risk.
Depending on the type of test used, screening may be recommended every one, three, five, or 10 years.
Colonoscopy
The benefit of this test is that when a polyp is found, it can be removed and the tissue sent for testing.Biopsiesare also taken during a colonoscopy, which can be analyzed to see if there are any concerning characteristics of the cells in the colon.
Colonoscopy should be repeated every 10 years.
Flexible Sigmoidoscopy
The limitation of this test is that only the sigmoid section can be seen, which means the physician will not visualize the rest of the colon. Adenomatous polyps further up in the colon can not be seen or removed.
Flexible sigmoidoscopy should be repeated every five years.
A thin tube is inserted approximately two inches into the rectum, and a CT scanner (a large imaging machine shaped like a donut) takes a series of images.
Virtual colonoscopy should be repeated every five years.
Stool-Based Tests
Astool testwill be used to look for signs of polyps and/or colon cancer in the stool. One such test, afecal occult blood test, looks for blood in the stool that can not be seen with the naked eye (called occult blood), which could be coming from a bleeding polyp.
A stool DNA test, also known as FIT (fecal immunochemical test)-DNA test, is one in which the stool is tested for genetic material from a polyp or colon cancer.
Depending on the type of test used, screening should be repeated every one to three years.
Adenomatous Polyp Treatment
When an adenomatous polyp is found, it likely will be removed in order to prevent it from growing and becoming a risk for cancer.
Certain polyps may be more challenging to remove, especially if they are larger, flat, or are located behind a flap or fold in the colon.
Polypectomy
Most adenomatous polyps will be removed through a procedure known as a polypectomy. Special tools on the colonoscope are used during a colonoscopy to remove polyps, including a wire loop. The loop might be used to snare the polyp at its base and remove it.
Sometimes this can result in bleeding, but it does not cause any pain, and in most cases, the bleeding will resolve. Serious complications after a polypectomy are not common.
Laparoscopic Surgery
If a polyp is too large to be removed during a colonoscopy, it might be necessary to uselaparoscopic surgeryto access it. This is also sometimes called minimally invasive surgery.
During laparoscopic surgery, small incisions are made in the abdomen (versus a large one in traditional surgery) to access the area where the polyp is located. Because the incisions are small, scarring is minimized and people often recover quicker than with open surgery.
Interpreting the Test Results
Interpreting a pathology report can be difficult, but the findings may be easier to grasp once you get a basic understanding of the terminology. The findings are largely based on the type, location, and characteristics of the removed polyps.
Types of Adenomas
There are three types of adenomatous polyps, each of which has different growth patterns and potential for malignancy:
Location
The location of a polyp can contribute to the risk of colon cancer in several ways.
Firstly, certain locations make it harder to spot a polyp, meaning that it may go undetected until the malignancy is advanced. Secondly, there are locations in the colon where a polyp is more likely to recur (return) even after it has been removed.
The pathology report might refer to the polyp based on its location:
Adenomatous polyps found in the distal colon are four times more likely to recur than those found in the proximal colon.
Polyp Characteristics
There are different terms that a pathologist will use to describe the physical or cellular characteristics of a polyp. These include:
Sessile serrated adenomas and traditional serrated adenomas have an increased risk of turning cancerous.
After an adenomatous polyp is found and removed, the next step is to discuss follow-up with the gastroenterologist. Although the overall risk may be small, all adenomatous polyps are risk factors for cancer.
The risk will depend on several factors, including how many polyps there were, how big they were, and what their characteristics were.
In most cases, follow-up screening will be advised. The interval will be based on current ACS/USPTF guidelines and other factors, such as your cancer risk.
A typical follow-up screening schedule might be:
Precancerous or Cancerous Biopsy for Polyps: What Happens Next?
Summary
An adenomatous polyp, also known as adenoma, is an abnormal growth in the colon that tends to look similar to surrounding tissues. Most adenomas are benign but some can turn cancerous. Risk factors include older age, smoking, and a family history of polyps.
Adenomas are commonly found during a colonoscopy and will often be removed to check for signs of cancer in the lab. Removing polyps also reduces the risk of them turning cancerous.
Routine colon cancer screening is recommended starting from the age of 45. The screening should be repeated every one, three, five, or 10 years depending on the type of test used.
A Word From Verywell
There is not much that can be done to avoid adenomatous polyps. While risk factors such as age or race cannot be changed, living a healthful lifestyle may helpreduce the risk of colon cancer.
Routine screening can also reduce the risk. A colonoscopy is considered the gold standard because it visualizes the entire colon and allows for the immediate removal of polyps if found.Removing a polyp means that it can’t continue to grow and become cancerous.
Don’t let inconvenience or thoughts of discomfort sway you from getting a colonoscopy. It is a minimally invasive procedure whose benefits greatly outweigh the risks. Health insurance may also cover it as anEssential Health Benefit (EHB)of theAffordable Care Act (ACA).
Adenomas that are not removed continue to grow. As they get larger, the risk of cancer increases. That said, most adenomatous polyps are benign (non-cancerous) and harmless.
All adenomas are considered pre-cancerous. However, just 5% or fewer adenomatous polyps actually progress to cancer over the course of 10 years.Learn MorePolyps and Your Cancer Risk
All adenomas are considered pre-cancerous. However, just 5% or fewer adenomatous polyps actually progress to cancer over the course of 10 years.
Learn MorePolyps and Your Cancer Risk
14 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Mitchem JB, Hall JF.Adenomatous polyposis syndromes: diagnosis and management.Clin Colon Rectal Surg.2016;29(4):321–9. doi:10.1055/s-0036-1584089
American Cancer Society.Colorectal cancer: facts and figures.
Wolff RK, Hoffman MD, Wolff EC, et al.Mutation analysis of adenomas and carcinomas of the colon: early and late drivers.Genes Chromosomes Cancer. 2018;57(7):366-76. doi:10.1002/gcc.22539
Lee SE, Jo HB, Kwack WG, Jeong YJ, Yoon YJ, Kang HW.Characteristics of and risk factors for colorectal neoplasms in young adults in a screening population.World J Gastroenterol.2016;22(10):2981–92. doi:10.3748/wjg.v22.i10.2981
Issa IA, Noureddine M.Colorectal cancer screening: an updated review of the available options.WJG. 2017;23(28):5086. doi:10.3748/wjg.v23.i28.5086
Shaukat A, Kahi CJ, Burke CA, Rabeneck L, Sauer BG, Rex DK.ACG clinical guidelines: colorectal cancer screening 2021.Am J Gastroenterol.2021;116(3):458-79. doi:10.14309/ajg.0000000000001122
Davidson KW, Barry MJ, Mangione CM, et al.Screening for colorectal cancer: US Preventive Services Task Force recommendation statement.JAMA. 2021;325(19):1965-1977. doi: 10.1001/jama.2021.6238.
American Society for Gastrointestinal Endoscopy.Understanding polyps and their treatment.
Pohl H, Robertson DJ, Mott LA, et al.Association between adenoma location and risk of recurrence.Gastrointest Endosc. 2016 Oct;84(4):709–16. doi:10.1016/j.gie.2016.02.048
American Cancer Society.Understanding your pathology report: colon polyps (sessile or traditional serrated adenomas).
American Cancer Society.Insurance coverage for colorectal cancer screening.
Bonnington SN, Rutter MD.Surveillance of colonic polyps: are we getting it right?World J Gastroenterol. 2016;22(6):1925–34. doi:10.3748/wjg.v22.i6.1925
American Cancer Society.Colorectal cancer risk factors.
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
